/Engine/Source/Runtime/Core/Public/Misc/Timespan.h
Return the result of subtracting the given time span from this time span.
A time span whose value is the difference of this time span and the given time span.
[FTimespan](API\Runtime\Core\Misc\FTimespan) operator- ( const [FTimespan](API\Runtime\Core\Misc\FTimespan) & Other ) const